参考文献

・DWIBS法(第一報)

Takahara T, Imai Y, Yamashita T, Yasuda S, Nasu S, Van Cauteren M. Diffusion weighted whole body imaging with background body signal suppression (DWIBS): technical improvement using free breathing, STIR and high resolution 3D display. Radiat Med. 2004 Jul-Aug;22(4):275-82. 

[983回被引用 (Google Scholar 2018.5)]

 

・DWIBS法(Review, Eur Radiol)

Kwee TC, Takahara T, Ochiai R, Nievelstein RA, Luijten PR. Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS): features and potential applications in oncology. Eur Radiol. 2008 Sep;18(9):1937-52. 

[413回被引用 (Google Scholar 2018.5)]

 

・DWIとDWIBS法の比較 (Magn Reson Imaging)

Mesmann C, Sigovan M, Berner LP, Abergel A, Tronc F, Berthezène Y, Douek P, Boussel L. Evaluation of image quality of DWIBS versus DWI sequences in thoracic MRI at 3T. Magn Reson Imaging. 2014 Dec;32(10):1237-41. 

RESULTS: Quality of fat suppression was significantly higher for DWIBS than for DWI both for free-breathing (score 3.48±0.65 vs. 1.76±0.96, p<0.0001) and respiratory-gated scans (3.17±0.77 vs. 1.72±0.73, p=0.0001). Similarly, artifacts were reduced with DWIBS (3.16±0.47 vs. 1.76±0.59, p<0.0001; 3.0±0.73 vs. 2.04±0.53, p=0.0001). Quantitative analysis showed higher STB with DWIBS (3.26±1.83 vs. 0.98±0.44, p<0.0001; 3.56±, 2.09 vs. 0.92±0.59, p<0.0001). Gating did not improve image quality and STB on DWIBS (p>0.05).

 

・Cancer BiomarkerとしてのDWIBS(NEOPLASIA)

Padhani AR, Liu G, Koh DM, Chenevert TL, Thoeny HC, Takahara T, Dzik-Jurasz A, Ross BD, Van Cauteren M, Collins D, Hammoud DA, Rustin GJ, Taouli B, Choyke PL.Diffusion-weighted magnetic resonance imaging as a cancer biomarker: consensus and recommendations. Neoplasia. 2009 Feb;11(2):102-25. 

[1456回被引用 (Google Scholar 2018.5)]

DWIのうち、DWIBS法が適切な方法として推奨されている。

 

 

・DWIBS法による全身MR-neurography (NEJM)

Yamashita T, Kwee TC, Takahara T. Whole-body magnetic resonance neurography. N Engl J Med. 2009 Jul 30;361(5):538-9. 

DWIBS法による均一な背景信号抑制により、世界で初めて全身の末梢神経走行を描出し得た。

 

・DWIBS法と造影MRIによる乳がん検出能の比較(ガイドライン策定以降)

- 2015年(Magn Reson Imaging)

Telegrafo M, Rella L, Stabile Ianora AA, Angelelli G, Moschetta M. Unenhanced breast MRI (STIR, T2-weighted TSE, DWIBS): An accurate and alternative strategy for detecting and differentiating breast lesions. Magn Reson Imaging. 2015 Oct;33(8):951-5. 

RESULTS: Unenhabced (UE)-MRI sequences obtained sensitivity, specificity, diagnostic accuracy, PPV and NPV values of 94%, 79%, 86%, 79% and 94%, respectively. CE-MRI sequences obtained sensitivity, specificity, diagnostic accuracy, PPV and NPV values of 98%, 83%, 90%, 84% and 98%, respectively. No statistically significant difference between UE-MRI and CE-MRI was found.

 

- 2016年(Radiology)

Bickelhaupt S, Laun FB, Tesdorff J, Lederer W, Daniel H, Stieber A, Delorme S, Schlemmer HP. Fast and Noninvasive Characterization of Suspicious Lesions Detected at Breast Cancer X-Ray Screening: Capability of Diffusion-weighted MR Imaging with MIPs. Radiology. 2016 Mar;278(3):689-97. 

RESULTS: Twenty-four of 50 participants had a breast carcinoma. With AP1 (DWIBS), the sensitivity was 0.92 (95% confidence interval [CI]: 0.73, 0.98), the specificity was 0.94 (95% CI: 0.77, 0.99), the negative predictive value (NPV) was 0.92 (95% CI: 0.75, 0.99), and the positive predictive value (PPV) was 0.93 (95% CI: 0.75, 0.99). The mean reading time was 29.7 seconds (range, 4.9-110.0 seconds) and was less than 3 seconds (range, 1.2-7.6 seconds) in the absence of suspicious findings on the DWIBS MIPs. With the AP2 protocol, the sensitivity was 0.85 (95% CI: 0.78, 0.95), the specificity was 0.90 (95% CI: 0.72, 0.97), the NPV was 0.87 (95% CI: 0.69, 0.95), the PPV was 0.89 (95% CI: 0.69, 0.97), and the mean reading time was 29.6 seconds (range, 6.0-100.0 seconds).

 

- 2018年(Jpn J Radiology)

Yamada T, Kanemaki Y, Okamoto S, Nakajima Y. Comparison of detectability of breast cancer by abbreviated breast MRI based on diffusion-weighted images and postcontrast MRI. Jpn J Radiol. 2018 May;36(5):331-339. 

RESULTS: The study included 87 patients with 89 breast cancer lesions ≤ 2 cm in diameter. The sensitivity/specificity for AP1 (The abbreviated protocols based on DWI) and AP2 (postcontrast MRI) for reader 1 was 89.9/97.6% and 95.5/90.6%, respectively, and those for reader 2 was 95.5/94.1% and 98.9/94.1%, respectively. The AUCs for AP1 and AP2 for reader 1 were 0.9629 and 0.9640 (p = 0.95), respectively, and those for reader 2 were 0.9755 and 0.9843 (p = 0.46), respectively.

国内施設からの最新論文。Kuhl教授の唱える短縮MRI(Abbreviated MRI)の手法で読影比較をした結果でも、DWI(本研究ではDWIBSを用いている)と造影MRIで差がないことが示された。

 

・Gd造影剤の沈着

*4 Kanda T, Nakai Y, Oba H, Toyoda K, Kitajima K, Furui S. Gadolinium deposition in the brain. Magn Reson Imaging. 2016 Dec;34(10):1346-1350. Review.

Gadolinium is highly toxic. Gadolinium-based contrast agents (GBCAs) consist of gadolinium ions and a chelating agent that binds the gadolinium ion tightly in order not to manifest its toxicity. Knowledge regarding gadolinium deposition in patients with normal renal function has advanced dramatically. Since 2014, increasing attention has been given to residual gadolinium known to accumulate in the tissues of patients with normal renal function. High signal intensity on T1-weighted images (T1WI) in the dentate nucleus, globus pallidus, and pulvinar region of the thalamus correlate roughly with the number of previous GBCA administrations. Pathological analyses have revealed that residual gadolinium is deposited not only in these brain regions, but also in extracranial tissues such as liver, skin and bone. The risks attendant with these deposits are unknown. Common sense dictates that gadolinium deposition be kept as low as possible, and that gadolinium contrast agents be used only when absolutely necessary, with preferential use of macrocyclic chelates, which seem to be deposited at lower concentrations.

2014年、MRI用 造影剤(ガドニウム、Gd)は脳に沈着すること、使用するほど沈着の度合いが高くなること(dose dependent:用量依存性)が報告された。その後の研究で2種類の造影剤(リニア型、マクロ環型)のうち、リニア型は10倍の沈着を招くことが判明。2017年8月に欧州で発売中止、同11月末に厚生労働省より「脳への残存が報告されていることを踏まえ、ガドリニウム造影剤を用いた検査の必要性を慎重に判断する。線状型は環状型より残存しやすいことが報告されていることを踏まえ、環状型 の使用が適切でない場合に投与する」と通知される [リンク]。